During a conference call to reporters on Monday, NASA chief financial officer David Radzanowski said the US space agency is requesting $30 million for preliminary studies into a mission to Europa for the year that begins Oct. 1. This is in addition to the $100 million Congress added to NASA’s budget to begin design work for a Europa mission last year.

In response to this news, and after 15 years exploring Europa mission concepts, JPL senior research scientist Robert Pappalardo said that most mission concepts have either been too small, too big or just too expensive, but “we believe we have now found the one that is just right.”

“We call this concept the Europa Clipper,” he said.

The Clipper concept has been an idea undergoing preliminary studies for some time, consisting of a Jupiter-orbiting spacecraft that will make multiple flybys of the Jovian moon Europa over a 3 year period. The spacecraft will dive deep into Jupiter’s radiation belts to fly over Europa’s surface approximately 45 times during its primary mission.

NASA’s Cassini spacecraft, which is currently orbiting Saturn, has carried out similar flybys of moon Titan, constructing a comprehensive map of its surface and measuring the moon’s thick atmosphere. The Europa Clipper will be focused on Europa in an effort to understand its habitable potential.

Europa’s Biological Mystery

Europa is thought to possess a vast sub-surface ocean beneath its thick icy crust, kept in a liquid state via tidal interactions with the gas giant. Possibly containing three times the volume of water held in Earth’s oceans — and because on Earth, where there’s water, there’s life — astrobiologists hypothesize that Europa’s ocean might be quite a cozy place for biology to gain a foothold.

“Europa’s ocean, to the best of our knowledge, isn’t that harsh of an environment,” said astrobiologist Kevin Hand, JPL’s Deputy Chief Scientist for Solar System Exploration, at a special JPL “Icy Worlds” media event on Monday.

Although Europa’s ocean may be up to 100 kilometers (62 miles) deep, the conditions at the bottom of that monstrous abyss may be akin to the environment at the bottom of Earth’s comparatively shallow Mariana Trench, the deepest region of the Pacific Ocean, which is 11 kilometers (6.8 miles) deep. Complex biology has evolved in Mariana’s cold, dark environment, so it’s not such a stretch to think that if there is life in Europa’s ocean, it may also be thriving, extracting energy not from the sun (via photosynthesis), but from chemosynthesis near hydrothermal vents.

Europa’s deep ocean owes its potential habitability to the moon’s size. It’s only the size and approximate mass of Earth’s moon and therefore has comparable gravity, ensuring ocean pressures are not too extreme for biology to evolve. It’s possible that, through the constant tidal heating of Europa’s core, the moon will also have hydrothermal vents spewing the heat and chemicals needed for Europan life.

What’s more, the icy crust of Europa would shield the ocean from the powerful radiation above.

“The radiation is stopped in the upper 10′s of centimeters to a meter” of icy crust, said Pappalardo, who is principal investigator for the Europa Clipper concept.

But this radiation isn’t all bad; the high-energy particles trapped in Jupiter’s magnetosphere trigger chemical reactions in Europa's surface ice layers, producing nutrients. Previous studies have shown that there may be an icy equivalent to plate tectonics continually refreshing Europa’s surface. Subduction zones may drag the collected nutrients below, supplying any hypothetical biosphere.

Europa’s life-giving potential is exciting — it has liquid water, a heat source and possible nutrient cycling — but the JPL scientists are keen to point out that the Europa Clipper concept will not be a life-hunting mission.

“The way we framed the Europa mission science objectives is not to specifically look for life, but to understand habitability; the ingredients for life,” said Hand. To search for life, argues Hand, a surface mission would be required, a technological feat that is currently out of our scope.

The instrumentation to be chosen to fly on the Europa Clipper spacecraft will observe Europa’s finest scales of a few feet, a scale that we currently know nothing about. Of particular interest will be what the famous reddish veins across Europa’s icy crust are composed of and whether they contain any organic compounds. Also, as the spacecraft will fly close to the moon, it could ‘sniff’ Europa’s possible water-rich geysers that the Hubble Space Telescope recently detected.

Like Saturn’s moon Enceladus, it’s possible that Europa has vents in its ice that eject subsurface water into space, leaving forensic evidence of the salts and other compounds it contains for any flyby spacecraft to collect and analyze.

Radiation Threat

For the Europa Clipper to explore the moon at such close proximity would require some tough shielding and clever orbital planning to protect the spacecraft’s sensitive electronics.

“It’s a jungle out there around Jupiter! It’s a jungle of radiation,” said Sara Susca, Europa Clipper payload systems engineer.

15 comments
:

I remember my father who was a boyscout in the 1930s coming to my school in the 60s and giving the.bellamy salute when we stood to pledge the flag. A ww2 vet but he never got the memo. Needless to say some of his friends let him know right away!!!!

Is it just a coincidence of history that we used the same salute the Nazis chose or did the concept originate from the same source, perhaps the Roman salute? I stopped believing in coincidences a long time ago.

Anybody lost anything on Europa? NASA (Never A Straight Answer) is a welfare program for scientists and engineers. It is absurd to be speind this amount of money and technical resource to find "life" on another planet when we have plenty of real problems on this planet. But what NASA is about is getting the budget, just like the rest of them.

In gun control happy Canada this child would probably been killed and the police would be out there whining about needing more money to hire more cops to not do what they didn't do in the first place; keep people safe.Fact is the police CANNOT keep anyone safe, they can only come in after the fact and clean up the mess and posture for the cameras.

Colorado has made pot "legal" BUT you have to PAY A VERY HIGH PRICE for it. It was much, much cheaper when you just went to your local street dealer for an ounce of pot vs get a "medical need" card and incur a doctor's bill on top of that and pay exorbitent rates to "buy" it legally. What for horsemanure is that I ask you? Political tap dance is what it is. If medical pot was made to sell at a reasonable cost vs hundreds an ounce that would be different....then every Tom, Dick and Harry could drive around stoned (as if they already don't do this) out there in Colorado. Leave it up to the greedy politicians to want to keep the excess tax money vs using it to spend on all the illegal aliens in Colorado and their upkeep!!! Then they would all stay out West and forget to invade the Eastern USA as they would have more of everything handed to them.

If they are some white scumbags. Believe it will be on across the country TV networks. But if they are Obongo people, you can hold your breath until you get purple in the face !USA ! USA ! USA ! USA ! USA !

The Pledge of Allegiance was the origin of Nazi salutes and Nazi behavior (that is one of the amazing discoveries of the historian Dr. Rex Curry). Francis Bellamy was an American socialist and his work influenced German socialism under Hitler. Robert Ellis (the person mentioned in the article) is not very bright and to this day he apparently has not addressed (nor even realized) that the Pledge of Allegiance was the origin of the Nazi salute and Nazi behavior. It was not an ancient Roman salute.